Trench ducts



Dec. 29 1970 J HALKOVICH ET AL 3,550,336

TRENCH DUCTS Filed Feb. 24, 1969 2 Sheets-Sheet 1 O G 6 I 0 COVER q 2 3. 2 ADJUST 4 TRIM HOLD DOWN !gl lb I (D {l A INVENTORS.

'LEO J. HALKOVICH STEPHEN M. JANIC AT TOR N EY.

Dec. 29, 1970 L HALKOVICH ET AL 3,550,336

TRENCH DUGTS Filed Feb. 24, 1969 2 Sheets-Sheet 2 o o 0} a o 0 COVER HOLD INITHlL ADJUST FINAL ADJUST o O Q P P 9 4| 4 43 COVER 4 HOLD INVENTORS. iq- 6 LEO J. HALKOVICH STEPHEN M. JANIC MWM ATTORNEY.

United States Patent Oflice 3,550,336 Patented Dec. 29, 1970 3,550,336 TRENCH DUCTS Leo J. Halkovich and Stephen M. Janic, Parkersburg, W. Va., assignors to Textron Inc., Providence, R.I., a corporation of Delaware Filed Feb. 24, 1969, Ser. No. 801,299 Int. Cl. E04f 17/08 U.S. Cl. 52-127 2 Claims ABSTRACT OF THE DISCLOSURE A trench duct having a cover adjusting system providing for an initial cover leveling adjustment right after the pour and a further final cover leveling adjustment after the concrete has hardened.

This invention relates to electrical underfloor distribution systems and in particular relates to improvements in trench ducts.

In one aspect, the invention relates to an improved trench duct for use with floors, such as cellular floors, which characteristically have large deflection upon pouring of the concrete and particularly to means providing for raising the cover to the level of the poured concrete even with the deflection in the order of one inch or more.

Another aspect of the invention relates to an improved trench duct having two independently operable mechanisms for vertically adjusting the cover, the first adjusting mechanism raising the cover when the floor is poured to compensate for floor deflection and the second adjusting mechanism providing for raising the cover after the pour has hardened to take care of irregularities in the floor which appear during the hardening process or for faulty initial adjustment.

It is one object of the invention to provide a trench duct of the kind in question wherein the adjusting mechanism has means providing for lateral and vertical stability both for the initial and final adjust, such stability insuring the adjusting function and minimizing the likelihood of misalignment and of tile breakage when the trench is in use.

Another object of the invention is to provide an improved duct of the kind in question wherein the mechanism for the initial adjust serves as a stable platform for the mechanism providing the final adjust.

Another object of the invention is to provide a trench of the kind in question wherein the cover adjusting mechanism cooperates with the hardened concrete to attain lateral and vertical stability of the exposed parts of the trench to thereby minimize the likelihood of misalignment, of difficult cover removal, and of tile breakage.

A preferred form of the invention will be described below in connection with the following drawings wherein:

FIG. 1 is a plan view of a trench duct incorporating the invention; FIG. 2 is a perspective view taken partially broken away and taken generally along the lines 2-2 of FIG. 1; FIG. 3 is an elevational sectional view taken along the lines 3-3 of FIG. 1; FIG. 4 is a plan view of a modified trench; FIG. 5 is a perspective view along the lines 5-5 of FIG. 4; FIG. 6 is a sectional elevational view along the lines 66 of FIG. 4.

The drawings and the description which follows refer to only one side of the trench duct. However, as will be understood by those skilled in the art, the trench has an identical structure on the opposite side.

The cover 1 has two pairs of cover hold-down screws 2 and two pairs of adjusting screw access openings 3 and a pair of tile trim hold-down screws indicated by the dash lines 4. A similar set-up is on the covers 1a and 1b for the adjacent sections of the trench.

The trench includes the elongated member 5 which is co-extensive with the length of the trench and comprises a horizontally extending bottom wall 6 adapted to be fixed to the cellular floor with which the trench is used, an upright outer wall 10 and a flange 11 connected to the top of the outer wall and extending horizontally outwardly therefrom.

The flange 11 carries a plurality of cover adjusting nuts 12. In the present case there being two of such nuts and these are respectively aligned with the access openings 3. For purposes of clarity, only one of the nuts .12 is shown in FIGS. 2 and 3. Preferably, these nuts are rib-nuts and are fastened to the flange by being crimped thereon with appropriate tooling. The thread axis of each cover adjusting nut extends vertically. The purpose of the nuts is to receive cover adjusting screws.

The flange 11 also has a plurality of apertures which (as"will be noted later) accommodate motion of cover hold-down nuts and tile trim hold-down nuts during the adjusting process. In the present instance, there are three of such apertures, two to accommodate cover hold-down nuts and one to accommodate a tile trim hold-down nut. In FIG. 2 these apertures are indicated at 13.

The trench also includes an elongated member 14 coextensive with the several sections of the trench and having a vertically extending inner wall 15 in sliding contact with the outer wall 10. A support platform 16 is connected to the top of the inner wall 15 and extends horizontally outwardly over the flange 11. A screed wall 17 is connected to the end of the platform 16 and extends vertically upwardly therefrom. During the pour of the concrete, the top of the screed wall is used as a screed line.

On the underside of the platform 16 is an anchor strip 20 which is preferably coextensive with the platform. The strip extends downwardly and outwardly beyond the screed wall. The strip 20 is spot welded to the platform.

The platform 16 mounts a plurality of cover-hold-down nuts in the present instance there being two of such nuts and one of which is indicated at 22. As shown in FIGS. 2 and 3, the nut 22 extends down through one of the apertures 13. The platform 16 also carries a single nut for use in locking down the tile trim and this is indicated at 23. As will be observed, the nut 23 extends through one of the apertures 13.

The cover 1 extends generally parallel the bottom wall 6 and over the support platform 16 with the edge 24 of the cover being spaced from the screed wall 17.

The gaskets 18 on the platform 16 carry the Z-shaped tile trim piece 25. The leg 26 of the trim piece extends upwardly between the cover and the screed wall. The cover 1 rests on gaskets 19 of the tile piece. The trim is reversible and extends over several trench sections.

The tile trim adjusting screw 4 bears on the tile trim and being threaded into the nut 23 locks the tile trim in position on the platform.

The cover, tile trim and member 14 form an assembly 29 which is held together as a unit by the cover holddown screws 2.

The tile trim 25 is provided with a plurality of openings such as the opening 30 (FIG. 3) and the platform 16 is also provided with similar openings 31 which are aligned with the openings 30. The openings 30 and 31 are in alignment with the access opening 3. Cover adjusting screws 32 are threaded into the nuts 12. As noted in FIG. 3, the head 33 of the screw bears against the cover 1 so that the head 33 supports the assembly 29.

A screw driver inserted through the access opening 3 and used to turn the adjusting screw 32 will cause the assembly, hence the cover, to be moved in a vertical direction.

As mentioned heretofore, the trench of the invention is particularly suitable for use with the cellular floors which are supported so as to have relatively wide spans and therefore are subject to more than the normal amount of deflection or sag upon the pouring of the concrete. The trench structure described herein is ideally suited for use with such floor-because the treach cover can be brought to the level of the concrete with the trench maintaining its structural integrity and without impairing its function conducting power and/or communication cables. The trench has been designed to effect cover adjustment even with floor sags in the order of one inch although the same structure can be utilized to provide necessary adjustments with larger deflections.

In connection with the vertical adjustment of the cover after the pour, it is to be noted that the various apertures 13 in the flange 11 are dimensioned so that the cover holddown nuts 22 and the tile trim hold-down nuts 23 make a close but sliding fit. The nuts cooperate with the apertures in the flange 11 and by preventing or minimizing lateral movement of the assembly 29 provide an anti-sway means. In addition, the wall and being in close engagement and being held in that position by the close fit of the nuts also assist in the anti-sway function. Therefore, the desired position of the various components is maintained even though the adjustment takes place over a large vertical distance.

The invention further contemplates an adjusting arrangement including not only the large initial adjustment-as heretofore described, but in addition a further or final adjustment which can be effected after the concrete is completely hardened. The dual adjustment arrangement is particularly suitable for applications where the pace of construction, the shape of the floor or the imposition of heavy loads before complete curing have the effect of causing floor distortions so that it is highly desirable or even necessary to have further cover adjustment to accommodate floor irregularities. The final adjust also provides a means for correcting the level of the cover in those instances where the cover, in the initial adjust, may not be correctly aligned with the screed level.

For the above purposes, the trench includes, structure heretofore described, but with additional structure which will permit the tile trim and cover to be moved vertically and thereby permitting the trench covers to be aligned to suit particular condition of the floor. In this structure the anchor strip heretofore described has a particularly important relationship with the final adjust in carrying out its function of providing stability.

The manner in which the foregoing is carried out will be described following in connection with FIGS. 4, 5 and 6.

With reference to FIG. 4 it will be seen that the cover 40 has a plurality of cover hold-down screws 41, initial adjust screws 42 (which correspond to the screws 32) and final adjust screws 43. In the embodiment shown, the tile trim hold-down screws are eliminated so as to permit free vertical movement of the tile trim 45.

With reference to FIGS. 5 and 6 it will be seen that the Z-shaped tile trim '45 instead of being supported by the member 46 (which corresponds to member 14) is supported by the shoulder 47 on the final adjust screw 43. The anchor strip 48 is spot welded to member 46 and extends downward and outwardly similarly as the anchor 20.

The cover hold-down screw 41 is threaded in the nut 49 crimped to member 46 and makes a close fit with the aperture 50 in the flange 51. The flange 51 corresponds to flange 11. The final adjust screw 43 is threaded in a nut 52 crimped to the member 46 and extending through a close fitting aperture 53 to the flange 51. The bottom of the nut 52 has a plastic cap '54 which prevents concrete from entering.

While I have shown the trench as including final adjust screws 43 adjacent opposite ends of each trench sec tion, it is pointed out that additional screws located intermediate the ends may be used depending upon the section length.

The cover 40, tile trim 45 and member 46 form an assembly 55 which is held together by the cover hold-down screws 41. The assembly 55 is supported on the head 56 of the initial adjust screw 42.

The initial vertical adjustment of the assembly 55 can be effected at the time of the pour by means of the screws 42 similarly as the screws 32 of the trench of FIGS. 1-4. The nuts 49 and 52 operating in the close fitting apertures 50 and 53 provide an anti-sway means for the assembly 55. The walls 57 and 58 also assist in the anti-sway function.

After the concrete has hardened, a final vertical adjustment of the cover of any one of the sections of the Itrench can be made. First, the cover screws are loosened to free the cover and the tile trim for vertical movement. Then the alignment of the cover with the level of the floor is accomplished by appropriately turning the respective screws 43.

The anti-sway feature mentioned above is an important part of the invention particularly for the initial adjust condition. The assemblies 29 and 55 are maintained in correct alignment throughout the several sections of 'the trench even though the vertical movement is over a substantial distance. There is virtually no lateral displacement of the assemblies during adjustment and furthermore any tendency for the assemblies to rock or tilt back and forth is minimized. The correct alignment along the various sections of the trench, of course, is mandatory from the standpoint of appearance and because misalignment would interfere with ease of cover removal and in the embodiment of FIGS. 4-6 would (in the absence of costly repair or replacement) interfere with or prevent the final adjust.

With reference to FIG. 2 it is to be noted that the trench is shipped from the factory with the member 14 in the down position, that is to say, with the platform 16 in engagement with flange 11. Also, the tile trim 25 is oriented so that its top most edge is fiush with the top of the cover and with the screed wall 17. The trench shown in FIG. 5 is also shipped with parts in the same position. Both trenches remain in this position during the construction period.

With the parts in such position the trench presents a unitary, strong, solid structure which is adapted to resist normal contact from workmen and equipment. However, when the trench is spread apart as by adjustment described above, the problem arises on how to maintain the integrity of the trench against contacts by a workman and equipment. The anti-sway mechanism and the anchor strips mentioned heretofore cooperate to provide for the necessary integrity. The manner in which this is done will be commented on below.

It is conventional in the pouring of a concrete floor to vibrate the concrete so that the same will run into and fill up the various cavities and contours which are present in the sub-floor structure or in the forms. With trenches of the kind described herein it is contemplated that during the initial adjust the concrete be vibrated so that the same runs into and intimately joins with the sides of the trench. For example, the concrete should be vibrated so that it flows into the space 33 below the flange 11 in contact with the side of the trench and in contact with the nut housings 12, 22 and 23. Also, the concrete should flow into the space 34 between the platform 16 and the flange 11 and contact with the side of the trench and with the nut housings 22 and 23.

With such flow of the concrete, the nut housings will be intimately joined therewith upon hardening of the concrete will provide for lateral stability for the assembly 29. Additionally, the concrete filling the spaces 33 and 34 will provide a solid, supporting foundation under the assembly 29 and provide a similar foundation under the nut housings. Consequently, any tendency for the assemblies to deflect substantially even under heavy load is reduced to an absolute minimum. Furthermore, with the nut housings imbedded in the concrete the housings provide an extremely rigid barrier against tilting of the assembly. Moreover, the nut housings and the concrete filling the spaces 33 and 34 also provide a substantial barrier against lateral displacement of the assembly.

Referring to FIGS. and 6 a similar disposition of concrete and similar function is contemplated. For example, concrete is to fill the space 60 below the flange 51 and the space 61 between the flange 51 and the member 46. Further, the concrete should be in intimate contact with the nut housings 49 and 52.

Oftentimes, however, concrete will not be properly vibrated and therefore will not flow into and fill up the spaces so as to make intimate contact with the sides of the trench and the various nut housing. This undesirable condition is aggravated by conventional floor construction practice. As is well known, after concrete is poured it takes approximately 28 days for the concrete to completely harden and attain its full strength. In building construction practice, however, the construction work goes on only after one or two days of setting time. Workmen and equipment then move on the floor. With concrete not properly disposed in the spaces and not having attained its full strength and with heavy loads on the trench sufficient to cause deflection, distortion or tilt of the assemblies 29 or 55, the effect would be to crush or crumble the newly formed concrete and simply aggravate the initial void condition. Thus, the support provided by the concrete would be lost.

With the present invention, however, the deforming or tilting of the assemblies is held to an absolute minimum or eliminated to the extent of avoiding the crushing of the newly formed concrete.

In the embodiments of FIGS. 2 and 5 the anchor strips cooperate with the poured concrete to provide necessary lateral and vertical stability. Each anchor strip extends outwardly and into the concrete at an angle and as such provide a substantial force against deflection of the member 14 and the member 46. Furthermore, the anchor will resist any tendency for either member 14 or member 46 to tilt or rock. The strip, therefore, functions to hold the assemblies (29 and in firm, stable condition. It will be appreciated that the anchor strips and the adjusting nuts function with respect to the concrete in the same manner, i.e., to prevent any tendency for deflection, or deformation or rocking.

Before closing, it is to be noted that with respect to the embodiment of FIG. 5 the concrete disposed in the spaces and 61 and surrounding the adjusting nuts provides for the assembly 55 to be a substantially solid, stable platform correctly aligned and oriented so that the final adjust can be made without difficulty and further that even in those instances where the concrete has not properly filled the spaces as aforesaid, the anchor strip functions so as to maintain the desired stability of the assembly 55.

We claim:

1. A trench duct to be imbedded in a concrete floor:

an elongated member co-extensive with the trench and comprising a horizontally extending bottom wall, an upright outer wall and a flange connected to the top of the outer wall and extending horizontally outwardly therefrom;

an elongated, vertically adjustable member co-extensive with the trench and having a vertically extending inner wall closely adjacent to said outerwall, a support platform connected to the top of the inner wall and extending horizontally outwardly over said flange and a screed wall connected to the end of the platform and extending vertically upwardly therefrom, the top of said screed wall being for use as a screed line;

an elongated anchor strip co-extensive with the trench and fixed to said adjustable member and extending outwardly beyond said screed wall to be imbedded in the concrete and provide lateral and vertical stability to said vertically adjustable member;

a cover extending generally parallel said bottom wall and over said support platform, the edge of the cover being spaced from said screed wall;

a tile trim piece underneath said cover and having a leg extending upwardly between said cover edge and said screed wall;

a plurality of access openings in said cover;

a plurality of openings in said platform and in said tile trim piece respectively in alignment with said cover access openings;

a plurality of apertures in said flange;

a plurality of cover hold-down nuts fixed to said platform, the thread axis of each nut extending vertically and each of the cover hold-down nuts making a sliding fit respectively with some of said flange a ertures to provide lateral stability to said vertically adjustable member and the nuts being for use in receiving cover hold-down screws and for use in being imbedded in the concrete to provide lateral and vertical stability to said vertically adjustable member;

a plurality of cover hold-down screws extending through cover access openings and engaged with said cover hold-down nuts and securing the cover, the tile piece and the adjustable member together as a unit;

a plurality of first cover adjusting nuts fixed to said flange, the thread axis of each nut extending vertically; and

a plurality of first cover adjusting screws respectively disposed in said first cover adjusting nuts and extending through said aligned platform and tile trim openings, each said first screw engaging the underside of the cover and each screw being respectively in alignment with cover access openings, the cover, the tile piece and the adjustable member all being supported by said adjusting screws and the turning of the first adjusting screws causing vertical motion of the cover, tile piece and adjustable member as a unit.

2. A trench duct to be imbedded in a concrete floor:

an elongated member coextensive with the trench and comprising a horizontally extending bottom wall, an upright outer wall and a flange connected to the top of the outer wall and extending horizontally outwardly therefrom;

an elongated, vertically adjustable member co-extensive with the trench and having a vertically extending inner wall closely adjacent to said outer wall, a support platform connected to the top of the inner wall and extending horizontally outwardly over said flange and a screed wall connected to the end of the platform and extending vertically upwardly therefrom, the top of said screed wall being for use as a screed line;

an elongated anchor strip co-extensive with the trench and fixed to said adjustable member and extending outwardly beyond said screed wall to be imbedded in the concrete and provide lateral and vertical stability to said vertically adjustable member;

a cover extending generally parallel said bottom wall and over said support platform, the edge of the cover being spaced from said screed wall;

a tile trim piece underneath said cover and having a leg extending upwardly between said cover edge and said screed wall;

a plurality of access openings in said cover;

a plurality of openings in said platform and in said tile trim piece respectively in alignment with said cover access openings;

a plurailty of apertures in said flange;

a plurailty of cover hold-down nuts fixed to said platform, the thread axis of each nut extending vertically and each of the cover hold-down nuts making a sliding fit respectively with some of said flange apertures to provide lateral stability to said vertically adjustable member and the nuts being for use in receiving cover hold-down screws and for use in being imbedded in the concreete to provide lateral and vertical stability to said vertically adjustable memher;

a plurality of cover hold-down screws extending through cover access openings and engaged with said cover hold-down nuts and securing the cover, the tile piece and the adjustable member together as a unit,

a plurality of first cover adjusting nuts fixed to said flange, the thread axis of each nut extending vertically;

a plurality of first cover adjusting screws respectively disposed in said first cover adjusting nuts and extending through said aligned platform and tile trim opeinings, each said first screw engaging the underside of the cover and each screw being respectively in alignment with cover access openings, the cover, the tile piece and the adjustable member all being supported by said adjusting screws and the turning of the first adjusting screws causing vertical motion of the cover, tile piece and adjustable member as a unit;

a plurality of second cover adjusting nuts fixed to said platform, the thread axis of each nut extending vertically and each of the second cover adjusting nuts making a sliding fit with some of the said flange apertures to provide lateral stability to said vertically adjustable member and each nut being for use in receiving a cover adjusting screw and for use in being imbedded in the concrete to also provide lateral and vertical stability to the vertically adjustable member; and

a plurality of second cover adjusting screws respectively disposed in said second cover adjusting nuts and respectively extending through said tile trim and cover openings, each second adjusting screw engaging the underside of the tile trim and supporting the same and the turning of the second adjusting screw causing vertical motion of the cover and tile piece as a unit with respect to said vertically adjustable member.

References Cited UNITED STATES PATENTS ALFRED C. PERHAM, Primary Examiner US. Cl. X.R. 

